A Study to Investigate Interchangeability of ABP 654 for the Treatment of Participants With Moderate to Severe Plaque Psoriasis

This is a multi-center study and will enroll approximately 480 participants. After eligibility confirmation, all participants will be randomized in a 1:1 ratio into 2 treatment arms: continued use of ustekinumab or multiple switches between ustekinumab and ABP 654 at Week 28. The randomization will be stratified by prior biologic use for psoriasis (yes versus \[vs\] no) at baseline (Week 0), geographic region, and baseline (Week 0) body weight. All participants will receive an initial 3 doses of ustekinumab on Day 1 (Week 0), Week 4 and Week 16. At Week 28, participants will be randomized to continue on ustekinumab or switching between ABP 654 and ustekinumab every 12 weeks. At Week 28, efficacy assessments will be conducted including evaluation of Psoriasis and Area Severity Index (PASI). Participants who do not achieve PASI 50 response or better improvement at Week 28 will be considered as run-in failures and will not be randomized at Week 28; these participants will complete End of Study procedures at Week 28. The run-in period will occur from Day 1 until randomization at Week 28. Those unable to complete the Week 28 visit or did not have a PASI assessment completed at Week 28 will be discontinued from the study. The total duration of study participation for each participant will be 68 weeks, with up to 4 weeks for screening and 64 weeks after the first investigational product administration.